Conventionally, chlorine oxides (e.g., chlorine, hypochlorous acid, chlorous acid, and chlorine dioxide) are primarily used for disinfection or sterilization of food for pretreatment in food processing operations, such as fresh perishable food including vegetables and fruits, and the facilities related to processing and production of processed food, such as containers, preparation/cooking machinery, and plant equipment. Of these, chlorine and hypochlorous acid, when reacted with organic compounds, are known to produce trihalomethanes, which are carcinogenic compounds. This, along with recent health-consciousness trend, has focused attention on acidified sodium chlorite (ASC) solution, which was developed in the United States of America and which possesses a high bactericidal effect and is less associated with trihalomethane-related adverse effects.
Reference 1: U.S. Pat. No. 6,524,624
To produce the above-mentioned ASC solution, an aqueous chlorous acid solution is mixed with an acid known as “generally recognized as safe” (GRAS) and adjusted to pH 2.3 to 3.2.
However, the main active component of the above-mentioned ASC solution, chlorous acid, decomposes a short time after preparation due to its low stability, thereby reducing its bactericidal potential. The above-mentioned ASC solution, therefore, needs to be prepared immediately before use.
This preparation procedure is not only inconvenient but also associated with the disadvantages resulting from production of chlorine dioxide gas, which is highly likely to have toxic effects on individuals who inhale it and corrosive effects on food-processing and cooking machinery and other related equipment.